Boresighting is used to accurately align avionic equipment mounted on a frame of an aerial vehicle. Examples of avionic equipment that require accurate alignment include inertial reference systems, guidance systems, radars, and other sensor and weapon systems. In order to properly operate and control the avionic equipment, the equipment on the aerial vehicle is aligned with respect to a reference axis or coordinate frame.
The typical boresight alignment tool includes an angular sensor used to measure the relative difference from a datum point of the aircraft to a target point of the aircraft to be calibrated. In addition, if the aircraft is not held rigidly in place, some form of sensor is needed to correct for aircraft body movement.
A higher level of accuracy is required in aligning a boresighting device to a mounting surface to be calibrated than is possible with current mounting methods. One problem is that the boresighting device and mounting system must be calibrated to each other in a factory, and cannot be replaced in the field without losing the required accuracy. An additional problem is that a platform or surface on which any type of calibration might be made can wear with time or not have the required surface accuracy for the required calibration. A further problem occurs when local coriolis and gravitation effects are different from the location where the equipment was originally calibrated. Depending on the type of sensor used in the boresighting device, this can significantly degrade the accuracy of the device.